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The need for a new digital mobile phone standard is being driven by the Internet, the development of corporate intranets, <注1> and the rapid growth in the number of mobile phone users, which some estimate could grow to 600 million worldwide by 2001.
In Europe and much of Asia, portable phones use the GSM, or global system for mobile communications, digital network, which can transfer data at speeds of up to 9,600 bytes per second. This speed is adequate for voice traffic, but is too slow for multimedia. <注2>
The proposed new system UMTS, which stands for universal mobile telecommunications system, is capable of transferring data at speeds of up to 2 million bytes per second. Manufacturers are waiting for standards to be set before gearing up for production of what will be the third generation of mobile phone equipment. There are two groups competing to have their technology adopted as the standard. In one camp<注3> are Nokia and Ericsson, the world leaders in GSM technology. The othersgroupsis headed by Siemens AG. <注4>
Nokia and Ericsson are proposing a system known as wide-band CDMA, or code division multiple access. <注5> The system proposed by the Siemenssgroupsis called time-division CDMA. The wide-band systems spreads communications over different radio frequencies. The time-division system divides conversations or datasintospackets of information, which are transmitted separately and reassembled at the receiving end.
Because the time-division method could result in loss of data or choppy<注6> conversations, most mobile phone industry experts consider the wide-band system to be the most appropriate technology for the new standard. |